A Tornado fighter bomber pulls up, while moving at high speed, causing a stall (a transient high-speed stall). The drop in air pressure around the wings causes the moisture in the air to condense and, in effect, form instant clouds. Jet fighters breaking the sound barrier, particularly when over water, often cause the same effect. In the case of the Tornado, the condition is enhanced by the swing wings automaticlally moving to adjust for the stall condition.
Posted: 10/01/2004